Earlier quoted context omitted.
Google doesn't allow disconnecting credit card from account unless you close it. That includes situation when you are just trying out free tier.
Does Google allow a privacy card that you can control whether an account is connected to it or not? That wouldn't help if someone racked up a ton of charges and Google bills daily, though.
And even in the US, you could presumably easily find all your Google accounts (including personal ones) locked until you pay the outstanding sum. Not something I'd risk, personally.